They are an exemption or freedom from something burdensome as a legal obligation for a recognised trade union ( i.e. one which is recognised "by an employer, or two or more associated employers, to any extent, for the purpose of collective bargaining (TULRCA 1992, s.178(3)).
Under UK law, trade unions do not have a positive right to strike and organise other forms of industrial action akin to that which exists in most other European countries. Instead, the law has granted the organisers of industrial action immunity from liability in tort. Essentially this means that, provided certain conditions are met, trade unions and their members and officers are protected from civil legal action by those adversely affected by industrial disputes. The reform of trade union law by the Conservative governments of the 1980s and 1990s had the effect of narrowing union immunity by introducing more exacting conditions before lawful industrial action could be taken. Thus, for action to retain immunity today, it must be preceded by a properly conducted strike ballot, notice must be given to the employer, action must be taken in furtherance of a trade dispute, and it must not be secondary action, targeted at third parties. The law has also been changed to allow trade unions themselves to be targeted in civil action and not just their individual members and officers. In some cases, this has led to unions suffering major claims for damages and to the sequestration of their assets. The terminology of ‘immunity’ is often criticized because it suggests that unions are above the law and uniquely privileged. In fact, the provision of statutory immunity is simply the way in which British law has provided unions and their members with the basic social and political right to withdraw labour.
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